Prominent jailbreak collective iPhone Dev-Team just released the latest version of their jailbreak tool, RedSn0w 0.9.15b1. If you are someone who has been keeping himself in the loop with the jailbreak scene, you should know that things aren't going so well with respect to the iOS 6 untethered jailbreak. But now, you'll be happy to know that there have been some positive development in the jailbreak front. iPhone Dev-Team's Redsn0w just received a massive update with more features than you can shake a stick at. Read more details about RedSn0w v0.9.15b1 after the jump.First off, let's manage your expectations first. NO, this version of Redsn0w will NOT give you an untethered jailbreak. And NO, it is still NOT capable of jailbreaking iOS 6 on A5+ devices (iPhone 4S, iPad 3, iPhone 5). However, there are significant new features that will surely make many users happy, or at least give hope to those who are losing hope concerning the jailbreak scene. iPhone Dev-Team just announced on Twitter that RedSn0w v0.9.15b1 can now be downloaded for Windows and Mac. They also wrote a lengthy post on their blog regarding the latest Redsn0w version. Below are the most noteworthy new features of RedSn0w v0.9.15b1.

RedSn0w 0.9.15b1 High-Level Features:

restore from any 5.x iOS to any other (up, down or the same) 5.x iOS on all devices as long as you have the correct blobs (see more below)

significantly more (very nerdy) info returned by “Identify” button when device is in Normal mode

tethered jailbreak of ATV2 supported (but the only thing available for it is the SSH2 custom bundle available here — no Cydia yet. Must use “Select IPSW” for tethered boot of ATV2 for now).

auto-exit WTF mode for older devices with broken buttons

any time a set of blobs is fetched remotely (from Apple or Cydia), redsn0w also saves them locally (and will check there first if you click “Local”)

for your future restoring convenience, you should also submit all of your past and present TinyUmbrella blobs to Cydia if you haven’t done so yet. Resubmitting is okay and won’t cause conflicts.

Wow! Were you able to catch all of that? Perhaps one of the most notable additions to this version of Redsn0w is the fact that it now properly jailbreaks iOS 6 on A4-based devices (iPhone 4, iPhone 3GS, iPod Touch 4G, Apple TV 2G), meaning Cydia will come with the jailbreak by default and need not be installed via a different procedure. If you have an iPhone 3GS, you can use RedSn0w v0.9.15b1 to jailbreak your device untethered.Apart from that, RedSn0w 0.9.15b1 now provides a more direct approach when downgrading firmware versions on A4 devices, provided that you have the necessary SHSH blobs. When downgrading A5 devices on the other hand, things become quite tricky. More details about A5 downgrading below:

redsn0w now lets you restore an A5+ device from any iOS5 to any other iOS5 as long as you have correct 5.x blobs for the starting (current) and ending points of the restore

APtickets eliminated “higher-version only” comparison of firmware restores (just like BBtickets did for the baseband)

example restores supported by redsn0w if you have the correct blobs: 5.1.1-to-5.0.1, 5.0.1-to-5.1.1, 5.1.1-to-5.1.1, 5.0.1-to-5.0.1

if you don’t have the blobs locally, let redsn0w try to fetch them remotely (redsn0w always tries both Apple and Cydia). Any succesful remote fetch also saves a local copy too.

You DO NOT QUALIFY for iOS5-to-iOS5 restores if you got to your current 5.x via an OTA update

the tickets saved by Cydia, redsn0w, and TinyUmbrella do not cover OTA update ramdisk images

even if they did, it’s the “wrong kind” of ramdisk (you’d need to start at that earlier pre-OTA FW)

devices fresh from factory or refurb may fall in the “does not qualify” category (your results will vary)

it’s okay if you previously got to 5.x via an OTA update, as long as your current 5.x was installed via a normal iTunes restore. All that matters is how you got to your current 5.x most recently

redsn0w detects an OTA/normal-restore APticket mismatch very early, so if you don’t know your status there should be no harm in trying. Any device in recovery mode after such a mismatch can boot normally again just by going back to “Even More” screen from the “Restore” screen (or use “Recovery Fix” if you quit redsn0w before doing that).

and so, redsn0w automatically flashes the currently signed baseband when it does A5+ restores, even if those basebands didn’t come with the original firmware

stay away from this if you have an unofficial unlock that isn’t supported by the newest baseband

the least-tested baseband update code in redsn0w is for iPad2,3 and iPad3,2. Please give any feedback on those iOS5 restores in the comments section below.

iPad2 owners (all three models) with saved 4.x blobs can use those instead, even from 6.x

if you have both 4.x and 5.x iPad2 blobs, you can always get to 5.x via the 4.x blobs, even if you’re currently on 6.x

you cannot get to 5.x from 6.x without the 4.x blobs (but you may still qualify for the iOS5-to-iOS5 restore described above)

if somehow you have 4.x blobs but no 5.x blobs, you can still go down to 4.x from 6.x

this only applies to iPad2 owners (they’re the only A5+ devices that ever had a public 4.x FW)

redsn0w still supports (but doesn’t require) jailbreaking A5+ devices at 5.0.1 and 5.1.1. Just head back to the first page after re-restoring to 5.x. It’s always much faster to jailbreak those FW versions with a freshly-restored device, before letting iTunes restore from a saved userland backup.

Sounds complicated? It is actually a lot more simple than you may think. You can downgrade your A5 iOS device if have saved the SHSH blobs for the present firmware that you are running and to the one you are trying to restore to. Also keep in mind that you can only downgrade if you are running an iOS 5 firmware (so you can only restore from iOS 5.x to iOS 5.x ex. 5.1.1-to-5.0.1), so if you have upgraded to iOS 6, then you are out of luck. In addition, you can't downgrade if you have used Over-The-Air (OTA) updates to get to your current iOS 5.x firmware. iPad 2 owners who have upgraded to iOS 6 can still downgrade to any iOS version (up to iOS 4) provided that the needed blobs are saved.

There are also information shared regarding Ultrasn0w and fetching SHSH blobs:

ultrasn0w isn’t yet updated for 6.x

by now you probably should be taking advantage of the extremely cheap IMEI-based unlocks of iPhones sold by established online retailers like http:://cutyoursim.com

still, IMEI-based unlocks don’t work in all cases. We’ll announce when ultrasn0w is ported up to 6.x

redsn0w will still hactivate your 3GS or iPhone4 if you run it before the device is activated. Due to the current tethered 6.x JB status, redsn0w now hactivates 6.x without requiring subsequent tethered boots. If you accidentally hactivate with redsn0w, use the “Deactivate” checkbox available from the Jailbreak screen, not the normal one in “Even more”

use this if you’re at 5.x or 4.x but without having saved your blobs when the window was open

this is only useful when Apple is no longer signing the firmware, otherwise Cydia/redsn0w “New”/TinyUmbrella blobs are superior (but you’re welcome to fetch your 6.0 blobs this way anyway)

fetching blobs in this fashion will automatically forward them up to Cydia, as well as save a local copy

Now we are aware that these are a lot of information to digest. If you have more questions, you can read the blog post of iPhone Dev-Team or you can leave a comment on this post and we will try our best to answer your queries. As per usual, we will be providing tutorials as well so be sure that you stay tuned.You can download RedSn0w 0.9.15b1 using the links provided below.